Mat cutting devices similar to that of the present invention are well known in the art, but each of these has a specific disadvantage which is obviated by the mat cutter of the present invention.
For example, U.S. Pat. No. 3,213,736 discloses a mat cutting device having a base and a single cylindrical guide rod along which a cutting head is displaceable, the cutting head having a pair of blades, one arranged vertically and the other an at angle, each blade being provided with a handle for pivoting the blade downwardly parallel to the guide rod for cutting the mat, and a mat holder fixedly mounted on the guide rod and extending the length thereof.
In another example, U.S. Pat. No. 3,628,412 discloses a mat cutter having a base and a single rectangular guide rod along which a cutting head having two vertically disposed blades is displaceable, with a mat holder mounted in the guide rod and extending the length thereof.
Further examples of the mat cutting art are disclosed in U.S. Pat. Nos. 3,897,706 and 3,996,827 which are so similar to U.S. Pat. No. 3,213,736, that any discussion of these patents would be redundant.
U.S. Pat. No. 4,022,095 discloses a mat cutter having a base and a guide rod in the form of an inverted V which holds down the mat while a cutting head, also in the form of an inverted V and having a blade arranged on one leg thereof, is displaced along the guide rod.
Citation of U.S. Pat. No. 4,096,631 is made for the record, but is so similar to U.S. Pat. No. 4,022,095, that once again, further discussions would be redundant.
U.S. Pat. No. 4,249,437 discloses having a movable belt on which the mat is carried and a pair of cutting heads mounted on guide rods and dispaceable therealong by a threaded rod to adjust the distance therebetween, the guide rods being mounted on a carriage which moves the cutting heads in the cutting direction, making a pair of parallel simultaneous cuts.
U.S. Pat. No. 3,967,519 discloses a pair of parallel guide rods mounted at their ends on parallel rails transverse to the rods, the rods being displaceable therealong. A carriage is slidably mounted between the guide rods and carries a rotatable cutting head indexed at 90.degree. intervals for cutting rectangles without moving the mat, the head being provided with a single blade and a non-tilting slide block or foot.
Finally, U.S. Pat. No. 3,973,459 discloses a single guide rod acting as a mat holder and carrying a cutting head having a blade arranged at a fixed angle.
These examples of the state of the art regarding mat cutting devices have the common disadvantage in that they are all complicated pieces of equipment, some of them extremely so, and all use some sort of hold-down device for the mat, some of which are part of the base and some of which are integral with the guide rod, none of which move with the cutting head, with the exception of the sliding foot of U.S. Pat. No. 3,967,519, which could scar the surface of the mat during the cutting operation, and which in addition, uses hold-down bars which are part of the base.
Some of the devices in the examples have handles on the cutting head for driving the blades into the mat, these handles making the cutting head cumbersome and hard to operate.
In some of the examples given, dual blades are used on the cutting head, one for making straight cuts and the other for making bevel cuts, adding to the cost and complexity of the device. In the cutting devices where only one blade is used, only one kind of cut can be made.